The day before yesterday we wrote about an in vitro study in which an extract of sumac killed cancer cells by accelerating their aging. Sumak, a spice of berry from the Rhus coriaria tree, may also be interesting for athletes, according to a 2016 human study. Athletes who use sumac reduce their breakdown of muscle tissue - and probably also the breakdown of tendons and joints.

Study
The researchers, who are by the way connected to King Saud University in the Kingdom of Saudi Arabia, got 40 fit students aged 15-25 years to exercise for 4 weeks every day for an hour with an intensity of 65-75 percent of the maximum heart rate.

Half of the test subjects received a placebo every day. The other half of the subjects drank a glass of 300 milliliters of sumac juice twice a day containing "580 mg of phenolic compounds and 80 mg of anthocyanins". The researchers made the sumac juice themselves. Here you can read how.

Results
After 2 weeks of supplementation, the subjects in the experimental group reported less pain during the training session than the subjects in the control group. The same was the case when the researchers, after 4 weeks of supplementation, measured the pain just after the training session.

You can see below how sumac reduces pain during and after intensive exertion. In weeks 2 and 4, the subjects in the sumac group had less creatine kinase and LDH in their blood than the subjects in the control group. That suggests that sumac reduces muscle damage.

The researchers also looked at the concentration of hydroxyproline in the blood of the test subjects. Exercise scientists consider the concentration of hydroxyproline in the blood as a marker for the breakdown of cartilage in joints and attachments.

It seems that sumac protects joints and attachments during exercise.

The figure above perhaps explains how sumac protects muscles and joints during exercise. In the blood of the subjects who received sumac, the antioxidant effect remained at the same level, while in the control group it decreased.

Conclusion
"The data obtained showed that administration of sumac juice for 30 days induced a significant reduction in muscle fatigue and pain, and enhanced muscle performance among healthy subjects following vigorous exercise interventions," the researchers summarize.

"Further research is needed to examine the mechanism by which the sumac can improve collagen fiber degradation."